Method of treating wire fabric



May 6, 1930. T H T 1,757,489

METHOD OF TREATING WIRE FABRIC Filed Nov. 26, 1928 5 Sheets-Sheet 1 y 1930. F. STEINHART 1,757,489

METHOD OF TREATINGWIRE FABRIC Filed Nov. 2a, 1928 Q :5 Sheets-Sheet 2 .[O [0b x x.

III III IIJ'L l.- I I I I I I I l0 l0 May 6, 1930. F. STEINHART 1,757,489

METHOD OF TREATING WIRE FABRIC Filed Nov. 26, 1928 3 Sheets-Sheet 3 Patente May 6, 1930 UNITED STATES PATENT OFFICE FERDINAND STEINHART, OF CLEVELAND, OHIO, ASSIGNOR, IBY IIIESNE ASSIGNMENTS,

TO THE LINDSAY WIRE WEAVING COMPANY, OF CLEVELAND, OHIO, A CORPORA- TION OF OHIO METHOD OF TREATING WIRE FABRIC Application filed November 26, 1928, Serial No. 321,898, and in Germany August 16, 1928.

This invention relates to seams for woven wire belts, particularly those which are tion of Fourdrinier paper making machines. 5 Usually seams for belts of this character have a stitching forming Wire which passes over one or more weft wires to reinforce the ends of the belt, while a closing wire is used for joining the ends of the belt. In most of these 1 seams, either the closing or stitching wire projects slightly beyond the ends or knuckles of the warp wires and are subjected to wear prematurely thus causing fracture of the belt at the seam.

Another seam used for this purpose is made by welding or soldering together the end weft wires to the warp wires and then passing a seam forming wire around the end weft wire on each end of the belt. An objection to the welding of weft wires is that the fabric openingsare apt to be clogged to an objectionable degree. As a result, drainage through the seam is retarded and defects result in the paper. An advantage of the soldered or welded seam, however, is the fact that a seam may be made without requiring the use of stitch forming wires which extend back into the belt on each side of the seam opening.

The present invention is directed toward a process of making a seam wherein the advantages inherent in the use of a welded soldered seam are obtained, and wherein the objections inherent in the seams first described are eliminated. To this end, my invention is concerned with a process of making a seam, for enabling it to be made in a satisfactory and expeditious manner.

A seam having these characteristics is illustrated, described and claimed in Letters Patent of the United States, No. 1,716,860, issued June 11, 1929, to Hamilton Lindsay. This invention is concerned with the process of making such seam in a simple manner without requiring the use of solder as will hereinafter be set forth.

While I have set forth an object of my invention as being concerned with the process of making a seam, nevertheless I also contemplate the use of this process for treating or preparing the edge of a woven wire fabric to make a selvage which eliminates all sharp edges of projecting wire ends. adapted for use in connection with-the operaare indicated at 10 and the weft wires are indicated at 11. The last weft wire in Fig. 1 is indicated at 11. To make a scam in accordance with my invention, the woven wire fabric is cut from the roll to the desired length, thereupon the fabric is laid upon a flat surface, and the end weft wire 11 is manually withdrawn from the fabric by pulling it upwardly from the body of the fabric while it is being supported upon the flat surface. The step of removing the last weft wire is shown in Fig. 2 wherein the top row of pickets or warp ends are inclined upwardly and laterally from the normal direction, as is indicated at 10*.

The fabric is then turned over with. the end being treated adjacent the edge of the flat surface, such as the edge of a worktable, and a tool indicated at 14, such as .a short rod, is passed along the pickets or warp ends 10 to make them incline in the opposite lateral direction to the pickets 10, as is shown in uch operation leaves the top and bottom rows of pickets crossing each other, but not in close-fitting engagement with each other. Moreover, each row of pickets is inclined away from the normal plane of the fabric.

The next step in my process is to bring the warp ends into close-fitting engagement with each other, and this may be accomplished by passing a roller 16 across the end of the belt. After this operation, the adjacent warp ends cross each other in pairs and form loops around the last weft wire 11".

The next step in my process is to join together the crossed warp ends. This is done by a welding operation in the following man- I ner. The end of the fabric is placed between the jaws of a vise with one or two weft wires projecting beyond the outer edge of the jaws. These jaws extend entirely across the width of the fabric and preferably comprise strips of copper which function not only to hold the fabric in proper position, but also to conduct the heat away from the warp ends and thereby to restrictthe extent of the welding operation. Disposed in front of and preferably beneath the clamp is a guideway 21 which extends parallel to the outer edges 22 of the clamping jaws. A carriage 23 is movable along this guideway and carries the nozzle 24 of a commercial gas blow torch.

I have found that a commercial oxy-acetylene blow torch produces satisfactory results. The intensity of the flame is adjusted to correspond with the hardness of the wire being welded, and the speed at which the blow torch is moved along the guideway is also governed by the hardness of the wire. In practice these two factors are quickly determined by a skilled operator as the welding operation is in process. The carriage may be moved along the guideway with the flame of the torch impinging upon the warp ends, and may be moved entirely across the width of the fabric in an expeditious manner. The wire used for paper making belts is sufliciently soft that the warp ends are automatically fused together as the blow-torch is moved across the abric I have found that after a little practice, it is possible to move the torch at such speed that the warp ends only are welded together, and that the welding heat is not sufficient to weld the last weft wire adjacent the fabric end. As a result of this operation, the warp ends are joined to ether to form loops, as is shown at 25, in ig. 5. This same procedure is followed with the other end of the belt, and then the two ends are brought together, and a seam forming wire shown at 26 in Fig. 6 is passed across the seam opening and between the loops at each end of the belt. The seam forming wire however, is shown as extending over the last weft wire at each end of the belt. 3

To make a seam wherein the seam forming wire passes through the warp end loops, such as is shown in Fig. 12, I provide means for restricting the flow of metal during the welding operation, so as to leave suflicient space in the loops through which a seam forming wire may be passed. This, I accomplish by weaving a combustible non-metallic thread as indicated at 40 in Fig. 7 next to the last weft wire at each end of the fabric. Thus, whenthe last weft wire is withdrawn, as is shown in Fig. 8, and the warp ends are brought together, as is shown in Figs. 9 and 10, the thread 40 is held between the loops. This thread being of combustible material is burned away during the welding operation. but remains in place for a suflicient length of time to prevent the flow of metal against the last weft wire and thereby to clog the openings in the loops. Thus, ample space between the loops is provided for enabling a seam forming wire to be passed through the loops at each end of the belt as is shown in Fig. 12. A

By means of this invention, the normally sharp projecting warp ends are eliminated, and a seam having sufficient mechanical strength can be obtained without the necessity for the use of stitch forming wires, which extend back into the belt on each side of the seam opening. Moreover, a satisfactory seam may be obtained with the aid of a single seam forming wire, which lies between the planes of the top and bottom surfaces of the belt. In this way, the seam is not subjected to wear upon the suction boxes of the paper machine until the body of the belt has become worn to an appreciable extent.

I claim:

1. A method of joining together the thread ends of a woven wire fabric, comprising inclining the thread ends in opposite directions until adjacent threads cross each other, and then progressively applying heat to the crossed ends to weld them together.

2. The process of forming loops in the edge of a woven wire fabric comprising progressively inclining one row of thread ends laterally in the same direction, then progressively inclining another row of thread ends in the opposite direction to cross the ends of adjacent warp wires, and then progressively applying heat along the edge to weld the warp ends together to form loops.

3. A process of forming loops in the edge of a woven wire fabric having warp and weft threads, comprising inclining the top row of warp ends laterally in the same direction, then inclining the bottom row of warp ends in the opposite direction until the ends cross each other, pressing the ends together and then progressively applying heat along the edge to weld the ends together to form loops.

4. A rocess of forming loops in a woven wire fabric having weft wires and warp wires, comprising removing the last weft wire by withdrawing it upwardly along the edge of thefabric so as progressively to incline the upper row of warp ends in one direction, then progressively inclining the bottom row of warp ends in the opposite direction until the warp ends are crossed, and then progressively applying sutficient heat to the edge of the fabric to weld the overlapping warp ends, the degree of heat being restricted to prevent the last weft wire from being welded to the fabric. 7

5. A process of making a seam for woven wire fabric comprising crossing the warp ends progressively at each end of the belt, applyends to form loops, and then ing heat progressively to the crossed warp assing a single seam formin wire through the loops at each end of the fa ric to make a belt. 6.. A process of making a seam for woven wire fabric comprising crossing the warp ends together at each end of the belt, applying heat progressively to the crossed warp ends to form loops and then passing a single seam forming wire through the loops at each end of the fabric to make a belt, the degree of heat being restricted to prevent the last weft wire from being welded to the fabric.

7. A method of finishing the edge of a woven wire fabric, having projecting wire ends, comprising progressively extending all of the upper wire ends in one direction and all of the lower wire ends in the opposite direction and then progressively applying heat along the crossed ends until they are welded together.

8. A method of treating the edge of a woven wire fabric having projecting thread ends, comprising progressively inclining the ends of projectlng ends in different directions to make some of the ends overlap, and then progressively applyin heat over the overlapped portions to weld t ein together.

9. A step inthe method of treating woven wire fabric having projecting wire ends, which consists in withdrawing the last trans verse wire upwardly and baokwardly toincline all of the top row of projecting ends laterally in the same direction, and with substantially the same degree of inclination.

10. A method of forming loops along the edge of a woven wire fabric, comprising weaving a non-metallic thread in the body of the fabric adjacent the last weft wire, with drawing the last weft wire, causing the project-ing warp ends tocross each other, and then applying suficient heat to the crossed warp ends to weld them together and to burn the non-metallic thread.

11. A method of treating the edge of a woven wire fabric, comprising weaving a thread of combustible material adjacent the last weft wire, removing the last weft wire from the fabric, and welding together the projecting warp ends, and utilizing suficient welding heat to burn away the combustible thread and to join together the projecting warp ends.

12. A method of treating the edge of a woven wire fabric having projecting wire ends, comprising crossing some of the wire ends, clamping the fabric in a vise with the crossed wire ends projecting slightly from the edge of the clamping jaws, and then applying heat of sufficient intensity to the projecting ends to weld them together.

In testimony whereof, I hereunto afix my signature.

FERDINAND STEHL I E 4% p 

